Phys 221 SI Worksheet: Circular and relative motion Supplemental Instruction Iowa State University Leader: Course: Instructor: Date: Justin Phys 221 Herrera-Siklody 9/10/14 1. The equations that describe the one dimensional motion with a constant acceleration are: 1 𝑣 = 𝑣0 + 𝑎𝑡 𝑥 = 𝑥0 + 𝑣0 𝑡 + 2 𝑎𝑡 2 𝑣 2 − 𝑣02 = 2𝑎𝛥𝑥 What are the equations that describe circular motion with constant angular acceleration and how do they relate to the one dimensional motion equations? 2. An object moving in uniform circular motion has an angular velocity of 1.25 rad/s. What radius is needed to have a tangential velocity of 3.75m/s? 3. For a radius of 1.5m and an angular acceleration of 2 rad/s/s what is the tangential acceleration? 4. An object at rest begins to rotate with a constant angular acceleration of 5.0 rad/s/s. If a point on the objects starts on the positive x-axis what angle does a line going from the center of the rotation to the point make with the positive x-axis after 1.2 seconds? 1060 Hixson-Lied Student Success Center 515-294-6624 [email protected] http://www.si.iastate.edu 5. A wheel with radius 4.00 m is turning about a horizontal axis through its center. The wheel starts from rest and undergoes constant angular acceleration in the counterclockwise direction. Point A starts at the lowest point on the wheel. After 2.50s the angular speed is 5.00rad/s. What are the magnitudes and direction of point A’s linear acceleration when it is at the left most point of its trajectory after making ¾ of a revolution, and the lowest point after making one revolution? How long does it take the wheel to make 2 revolutions? 6. A boat must cross a 200m wide river and arrive at a point 120m downstream from where it starts. To do so, the captain angles the boat 45 degrees upstream. If the boat can travel 4m/s in still water, what is the speed of the current? How long does the journey take?